1. Field of the Invention
The present invention relates to an endoscopic system for the display of a three-dimensional picture which displays a picture taken as a stereoscopic picture in a body cavity so that the picture can be switched to a planar picture (two-dimensional picture: 2D) or a stereoscopic picture (three-dimensional picture: 3D).
2. Description of the Related Art
Recently, in display devices such as televisions, devices which can display stereoscopic pictures (3D pictures) showing a feeling of depth therein have been coming into wide use. Current endoscopic devices generally display planar pictures (2D pictures). An observational diagnosis or treatment operation is performed with an estimated or experiential sense of distance for an observation spot and the operation of a treatment instrument such as a forceps that are shown on a screen simultaneously with the observation of displayed images taken by a photography section at the distal end of an endoscope. Thus, there have been demands from users including surgeons for the reduction of the burden of the operation associated with the stereoscopic pictures to supplement the sense of distance.
A naked-eye-type method for observing 3D pictures with the naked eye has been suggested as one known video method for 3D pictures. According to this method, the positions to stand before a display screen are extremely limited. Thus, video methods for 3D pictures by monitor observation that are mostly used are naked-eye-type methods using polarized glasses or liquid-crystal shutter glasses. Among these methods, the method that uses the polarized glasses is the mainstream method in medical fields where more than one monitor are disposed in many cases.
The above-mentioned 3D pictures allow a feeling of depth of an observation spot to be obtained and are therefore suitable to the observation of the inside of a body cavity. However, 2D planar pictures may be easier to view depending on display contents, for example, when an observation object is located extremely close or when a treatment instrument or an organ which is not an observation object is located extremely close. Jpn. Pat. Appln. KOKAI Publication No. 2012-249168 suggests a technique for switching between a 3D picture and a 2D picture.
The presence of a switching time is a challenge in the switch between a 3D picture and a 2D picture. That is, the original picture on a monitor screen disappears when a switching operation is performed with a switch, and a switched picture is displayed after a time. That is, in the case of a switch from a 3D picture to a 2D picture and vice versa, there may be a slight time in which the display is off. This is because when the format of a video signal to be input is switched, the monitor first detects a format, and then receives video data to be displayed on the basis of the detected format. However, if the screen turns off even for a slight period during the operation of the endoscopic device, the efficiency of treatment or diagnosis deteriorates, and the burden on a surgeon or a patient increases.
It is therefore an object of the present invention to provide an endoscopic system capable of switching between a 3D picture and a 2D picture in which a screen non-display time during the switch between a 3D picture and a 2D picture is reduced.